.mm_header_app {
  width: 100%;
  height: 44px;
  background: #ff841d;
  position: absolute;
  left: 0;
  top: 0;
  padding-left:50px;
  padding-right:50px;
}
.mm_container {
  padding-top: 44px;
}
.mm_header_app a {
  width: 50px;
  height: 44px;
  position: absolute;
  top: 0px;
}
.mm_header_app .header_back {
  left: 0px;
  background: url('../img/back.png') no-repeat;
  background-position: center;
 background-size: 20px;
}
.mm_header_app .header_home {
  right: 0px;
  background: url('../img/header_app.png') no-repeat;
  background-size: 32px;
  background-position: center;
}
.mm_header_app h2 {
  width: 100%;
  font-size: 20px;
  color: #fff;
  font-weight: bold;
  height: 44px;
  line-height: 44px;
  text-align: center;
}
.sit-main {
  width: 300px;
  margin: 10px auto;
  float: none;
}
.sit-main a {
  padding: 10px 8px;
  background: #f4f4f4;
  border:1px solid #bfbfbf;
  float: left;
  margin: 0 0 5px 5px;
  color: #000000;
}
.sit-main a img {
  margin-right: 5px;
  vertical-align: middle;
}